Throttle



N. T. M KEE Aug. 2, 1932.

THROTTLE Filed Sept. 13, 1928 2 Sheets-Sheet 1 IN VEN TOR.

BY 0 %%p A TTORNE Y.

Aug. 2, 1932. N. T. MCKEE. 0,

' THROTTLE Filed Sept. 15. 1928 2 Sheets-Sheet 2 ,7. X Z m N A/ 7/ A7 INVENTOR,

BY A N Q Q I m ATTORNEY.

Patented Aug. 2, 1932 UNITED sTATEs PATENT OFFICE v NEAL T. MCKEE, OF BRONXVILLE, NEW YORK, ASSIGNOR TO AMERICAN THROTTLE COMPANY, INC., OF NEW YORK, N. Y.

THROTTLE Application filed September 13, 1928. Serial No. 305,725.

This invention relates to locomotive throttles of the so-called multiple type forming the subject of a number of United States patents such e. g. as 1,662,955 to R. M. Brown, and has for its purpose the improvement of devices of that class.

The invention is illustrated in the accompanying drawings in which Fig. 1 is a composite view, the left half showing the improved device in front elevation and the right showing it in central vertical section, the apparatus being located in the upper portion of a locomotive smoke-box a portion of which is also shown; Fig. 2 is a section on line 22 of Fig. 1; Fig. 3 is an enlarged view of a portion of Fig. 2; Fig. 4 is a top view of one of the valves; Fig. 5 is a section on line 55 of Fig. 3; Fig. 6 is a section on line 66 of Fig. 3; and Fig. 7 is a fragmentary view showing a modification, the view correspond ing to that of Fig. 3.

The invention relates, as indicated above, primarily to locomotives although its use is not limited in this respect. The body of the locomotive boiler appears at 1, the smoke-box sheet being shown at 2. The boiler is separated from the smoke-box by the flue sheet 3 from which extend backward toward the fire-box (not shown), the fines 4&. Within the lines 4: are located the tubular superheater elements 55 whose forward ends are turned upward as at 6-6 and are connected to the superheater header 7. The superheater header has steam delivered to it by the dry pipe 8. 11 represents the connections for the steam pipe 12. There are, of course, two such connections and pipes, one on either side. 9 indicates the locomotive stack and 10 the petticoat pipe extending downwardly from it. All of this is in accordance with the ordinary and well-known arrangement.

The function of this arrangement may be briefly stated as follows: Steam from the boiler is delivered by the dry-pipe 8 to certain chambers in the header 7 and flows from them into the superheating tubes or elements 5-5. The gases flowing through the fines 4 heat the steam on its course through the superheater elements 55 and deliver it back to certain other chambers in the header 7 in a superheated state.- From these chambers it flows to the two engines on either side of the locomotive through the steam pipes 12.

It has become quite increasingly common within the last year or two to control the flow ofsteam from the superheater header to the engines by means of throttling means located between the superheater header and the steam pipes. The arrangement that has found most favor is one in which a plurality of comparatively small throttles is used which may be opened successively to supply the varying amounts of steam needed. My in-. vention retains this general arrangement, but provides an improved form of throttle.

The superheated steam on its way to the pipes 12 passes first into the transverse chamber 13 which extends from one end of the header to the other as will be clear from an inspection of Fig. 1. Below this chamber 13 is a second horizontal chamber 14 separated from 13 by the partition 15. This partition 15 has a plurality of ports 16-16, their number being a matter of choice. In the particular form illustrated there are six of them. These ports are preferably lined with bushings 1717, the upper end of which is formed into the valve seats 18.

In Fig. 3 is shown an enlarged view of one of these valves to which reference will now be made. The valve proper 19 engages the seat 18 and is equipped at its upper end with a piston 20. This piston reciprocates in the cylindrical space 21 of the removable cap 22. The valve has a port 23 controlled by the pilot valve 24. From the lower end of the port 23 channels 25 extend downward through the body of the valve. A stem 26 extends downward from the valve body, this stem as well as the body of the valve being perforated with stem 27 extending through the perforation. The pilot valve 2a is clamped between the nut 28 and a shoulder on the stem 27. A. shoulder 29 on the stem 27 engagesthe lower end of stem 26 when stem 27 is moved upward. An enlargement 30 of the stem is laterally slotted at 31 and the lower cylindrical end 32 of the stem 27 extends into a corresponding cavity 33 in the bottom of the chamber 14.

The slot 31. is engaged by the roller 34 (see Fig. 6) carried on the pin 35. This pin is carried by the two arms 3636 of the arm 37 keyed to the shaft 38.

The upper face of valve 19 is recessed, and extending laterally from this recess are two small cavities 39.

The lit of the piston portion 20 of the valve 19 in the cylindrical cap is such that steam can readily leak into the cap but that when the pilot valve 24 is open it cannot leak fast enough past the piston into the hollow of the cap to build up any material pressure.

The shaft 38 extends outward through a stufling box through the smoke-box sheet and carries on its outer end an arm %1 from which extends backward to the cab the throttle rod for manipulation by the engineer.

The operation of the device is as follows: As long as all the valves are closed, steam leaking past the loosely fitted pistons 20 into the hollow caps keeps the valves seated. lVhcn the engineer manipulates the throttle lever to rotate the shaft 38 in a counter clockwise di 'ection as viewed in Fig. 3, the roller 34 on pin 35 raises stem 27 of the first valve to be operated and opens the pilot valve 24:. This releases the steam from the cavity in the cap 22, and the valve 19 is the .eby put into a balanced state so that on further rotation of the shaft 38 the valve 19 is easily raised. This occurs when the shoulder 29 engages the lower end of the stem 26. The extension 32 moving in the cavity 33 acts as a guide in this operation. When the throttle 19 is opened. steam flows from chamber 13 into the chamber 14 and thence through connections 11 and pipes 12 to the engines.

The closing of the throttle occurs by a rotation of the shaft- 38 in the reverse direction, that is. in a clockwise direction and it will he noted that the valve is positively closed. The roller 34; engages the lower ide of the slot 31 and pulls downward the pilot valve 24 which, engaging its seat. pulls downward the main valve.

Each of the valves in the series is constructed and operates like the one'described in detail above. Preferably the arrangement is such that the valves do not open simultaneously but in some order other than simultaneous, the exact order being a matter of choice. If desired, they may all open serially or they may open two at a time and in general any preferred arrangement can be adopted. Preferably also all or most of the pilot valves open before the first main valve is opened.

lVhen it becomes necessary to grind throttles 19 to their seats, caps 22 are taken off, nuts 28 and pilot valves 24 are removed, and the valves 19 are ground to their seats by rotating them by means of a tool engaging the two recesses 39.

To grind the pilot valves 24 to their seats the valves 19 are taken out and Valves 24 are then ground each to its seat by means of a dummy stem like 27 being used for this purpose. It is thus unnecessary to remove the stems 27 for the grinding of either of the throttles or of the pilot valves. This is a great convenience as the removal and insertion of these stems is rather troublesome.

Instead of guiding the lower end of the stem 27 bythe means shown in Fig. 3, this may be done by the alternative arrangement shown in Fig. 7. Here the bottom wall of the chamber let instead of carrying a boss with a hollow'interior 33 is perforated and a pin 42 is riveted into or secured in some other way to the bottom wall in a vertical position. This pin extends into a correspondingly shaped cavity 43 in the lower end of the stem 27.

Obviously a number of variations may be introduced in practicing my invention without losing its spirit.

I claim:

In apparatus of the class described, the combination of an elongated casing arranged transversely in the upper part of a locomotive smoke-box, a. horizontal partition in said casing having a plurality of alined ports along its length, a corresponding number of removable caps in the wall above the partition, each can having a cylindrical cavity alined with the associated port, a plurality of poppet valves each adapted to close a port and having a cylindrical portion fitting loosely and reciprocating in the corresponding cap cavity, each of said valves having a central bore with a passage extending from a point near the upper end of the bore to the lower face of the valve, stems extending through said bores and each provided with a shoulder adapted to engage and raise its Valve, a. pilot valve on the upper end of each stem to control the upper end of the bore, removable means to retain the pilot valves on the stems, guides on the lower wall each engaging the lowerendof a stem, and means to raise said rods seriatim thereby opening the pilot valves and main valves and to lower the rods seriatim thereby closing both sets ofvalves.

NEAL T. MCKEE.

or ..o 

